[Original article]
1
Sonographic Renal Length and Volume of Normal Thai Children versus their Chinese 2
and Western Counterparts 3
Running title: Renal Length and Volume of Normal Thai Children 4
5
Chantima Rongviriyapanich, MD1, Thanarat Sakunchit, MD1, Chirawat Sudla, BSc, RT1, 6
Supamas Mungkung, MD2, Napapong Pongnapang, PhD3, Chai Hong Yeong, PhD 4* 7
1Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, 8
Bangkok, Thailand 9
2Department of Radiology, Mueang Narai Hospital, Lopburi 15000, Thailand 10
3Department of Radiological Technology, Faculty of Medical Technology, Mahidol 11
University, Bangkok 10700, Thailand 12
4School of Medicine, Faculty of Health and Medical Sciences, Taylor’s University, Selangor 13
47500, Malaysia 14
15
Corresponding author 16
Chai Hong Yeong, PhD 17
School of Medicine, Faculty of Health and Medical Sciences, 18
Taylor’s University, Selangor 47500, Malaysia 19
Tel. + 60167016875 20
E-mail: [email protected] 21
https://orcid.org/0000-0003-1572-4143 22
23
Accepted Article
Abstract 24
Background: Renal size is an important indicator in the diagnosis of renal diseases and 25
urinary tract infections in children.
26
Purpose: The purpose of this study is twofold. First, it aimed to measure the renal length and 27
calculate the renal volume of normal Thai children using two-dimensional ultrasonography 28
(2D-US) and study their correlations with somatic parameters. Second, it aimed to compare 29
the age-specific renal size of normal Thai children with the published data of their Western 30
and Chinese counterparts.
31
Methods: A total of 321 children (150 boys, 171 girls aged 6–15 years) with a normal renal 32
profile were prospectively recruited. All subjects underwent 2D-US by an experienced 33
pediatric radiologist and the renal length, width, and depth were measured. Renal volume was 34
calculated using the ellipsoid formula as recommended. The data were compared between the 35
left and right kidneys, the sexes, and various somatic parameters. The age-specific renal 36
lengths were compared using a nomogram derived from a Western cohort that is currently 37
referred by many Thailand hospitals, while the renal volumes were compared with the 38
published data of a Chinese cohort.
39
Results: No statistically significant difference (p < 0.05) was found between sexes or the right 40
and left kidneys. The renal sizes had strong correlations with height, weight, body surface 41
area, and age but not with body mass index. The renal length of the Thai children was 42
moderately correlated (r = 0.59) with that of the Western cohort, while the age-specific renal 43
volume was significantly smaller (p < 0.05) than that of the Chinese children.
44
Conclusion: Therefore, we concluded that the age-specific renal length and volume obtained 45
by 2D-US would vary between children in different regions and may not be suitably used as 46
an international standard for diagnosis, although further studies may be needed to confirm our 47
findings.
48
Accepted Article
49
Keywords: 2-dimensional ultrasonography, Children, Renal length, Renal volume, Thailand 50
51
Key message 52
Question: What is the normal renal size of Thai children and is the renal nomogram 53
comparable to those of Western and Chinese cohorts?
54
Finding: The renal length of Thai children was moderately correlated with that of Western 55
children, while the age-specific renal volume was significantly smaller than that of Chinese 56
children.
57
Meaning: Renal size in children can vary among regions and sociodemographic backgrounds;
58
hence, a local reference standard is needed.
59 60
Graphical abstract 61
r Linear Regression Equation Age 0.719 y = 5.95 + 0.26*Age Height 0.809 y = 2.03 + 0.05*Height Weight 0.701 y = 6.93 + 0.05*Weight BMI 0.394 y = 7.08 + 0.09*BMI BSA 0.763 y = 5.65 + 2.55*BSA
r Linear Regression Equation Age 0.625 y = 16.88 + 5.45*Age Height 0.753 y = -76.93 + 1.09*Height Weight 0.786 y = 27.54 + 1.30*Weight BMI 0.572 y = 18.94 + 3.07*BMI BSA 0.813 y = -3.68 + 66.93*BSA
B. Correlation between mean renal volume and somatic parameters:
A. Correlation between mean renal length and somatic parameters:
Correlation between Renal Length and Volume with Somatic Factors
Nomogram of Western Cohort (n = 122)
(Han and Bobcack, 1985)
Nomogram of Chinese Cohort (n = 3,376) (Leung et al, 2007) Ultrasound Imaging
1. Renal Length (L)
2. Renal Volume = L x Width (W) x Depth (D) x 0.523 321 healthy Thai children (6 – 15 years) were recruited
150 171
The age-specific renal volume was significantly smaller (p < 0.05) than the Chinese
children
Compared to
Results
62
Sonographic renal length and volume of normal Thai children versus their Chinese and 63
Western counterparts 64
Accepted Article
Introduction 65
66
Renal size assessment is vital in the evaluation, diagnosis and follow-up of pediatric patients 67
with kidney, ureters and bladder (KUB) pathology, as well as for urinary tract infection (UTI) 68
as many renal disorders will affect the kidneys growth and development [1-7]. Normative 69
standards for assessing renal size are commonly used in clinical practice. These standards 70
rely upon comparison of the renal lengths or calculated volumes, or both, with a variety of 71
somatic factors such as body surface area (BSA), weight, height, sex and chronological age 72
[7].
73 74
Two-dimensional ultrasonography (2D-US) is a method of choice for measurement of kidney 75
sizes in children due to its non-invasiveness, non-ionizing, cost-effective and can be 76
performed at the hospital bedside [1,8,2,9,3,10,5,7]. Although renal volume is a more 77
accurate parameter in reflecting the renal growth, renal length is more commonly used for 78
diagnostic purposes because it can be easily measured and the results can be obtained in situ 79
without complex calculations [8,6]. However, renal length measurement is prone to inter- and 80
intra-observer errors, besides having poor consistency due to the complex shape of the kidney 81
[4,6]. Measuring renal volume is a better way in detecting abnormalities, especially when 82
biochemical tests show normal results or when the disease cannot be visualized on ultrasonic 83
images. It is also an excellent predictor of renal function and correlates well with other body 84
parameters [8,6].
85 86
Renal size and growth may or may not be significantly influenced by ethnicity. According to 87
Leung et al. [11] who studied the nomogram of renal volume calculated using the ellipsoid 88
formula of 2D-US in normal Chinese children, no significant difference was found in renal 89
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size and growth when compared to the data of Western children obtained by Schmidt et al.
90
[5].
91 92
Currently, the growth chart of age-specific renal length proposed by Han and Babcock [12], 93
which was derived from the Western population is used as a reference by many Thai 94
radiologists and nephrologists in monitoring kidney development of their patients. To our 95
knowledge, there was no study on the renal size and its relationship with somatic parameters 96
among normal Thai children to date. This study, therefore, aimed to measure the renal length 97
and volume of normal Thai children using the ellipsoid formula of 2D-US and to derive their 98
growth chart. The data were then compared to the published data of the Western [12] and 99
Chinese [11] cohorts. The correlations between the renal size (i.e. length and volume) and 100
somatic parameters (i.e. sex, age, height, weight, BSA and body mass index (BMI)) were also 101
studied.
102 103 104
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Methods 105
106
1. Subjects 107
108
This study was approved by the Medical Ethics Committee of the *blinded info*. A total of 109
321 children, comprising 150 boys and 171 girls aged between 6 and 15 years were 110
prospectively recruited from the central region of Thailand. The subjects were divided into 111
respective age groups as shown in Table 1. The demographic data, i.e. sex, date of birth, 112
height, weight, as well as renal profile of the subjects were collected before the 2D-US 113
examination.
114 115
Subjects who had normal renal profile as evident from a blood test report and did not have 116
current urinary symptom were recruited into the study. Exclusion criteria include a history of 117
known renal disease, hematuria, UTI, increased levels of serum urea and creatinine, any 118
history of renal surgery and clinical symptoms of dysuria. Subjects were excluded if the 2D- 119
US image quality was too poor to be interpreted or when abnormalities, such as congenital 120
anomaly, renal mass and hydronephrosis were detected. Children with abnormal renal length, 121
such as the left kidney was significantly longer than the right (≥ 10 mm) or the right kidney 122
was significantly longer than the left (≥ 7 mm), were also excluded due to the possibility of 123
an underlying pathology [13]. Informed consent was obtained from the parents of all subjects.
124 125
2. Ultrasonographic Data Acquisition and Volume Measurement 126
127
2D-US was performed by a pediatric radiologist with 13 years of experience using the 128
Voluson E6 ultrasonography system with 2 - 5 MHz transducer (GE Healthcare, Chicago, 129
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Illinois, USA). The subjects were examined in supine oblique position. The maximum renal 130
length was measured along the longitudinal axis of each kidney. The width and thickness 131
were measured in the transverse plane perpendicular to the longitudinal axis of the kidney at 132
the level of the hilum. A sample of the ultrasound image is shown in Fig. 1. The renal volume 133
was calculated using the ellipsoid formula as following:
134 135
Renal volume = length x width x depth x 0.523 136
137
3. Statistical Analysis 138
139
Sample size was presented at 95% confidence interval (CI) of the true mean. A previous 140
study of children under age 18 showed that total renal volume increased as age increased with 141
the mean of 124 – 230 ml (standard deviation, SD: 10.4 – 17.0) [11]. Using SD of 16.5 ml 142
and a mean estimation error of 5.5 ml, this study required a sample size of at least 35 children 143
in each age group as calculated by the nQuery Advisor software (Statsols, Boston, 144
Massachusetts, USA). As this study comprised 9 age groups, the calculated total sample size 145
was 315 subjects.
146 147
Renal dimensions (i.e. length, width, thickness and calculated volume) were presented using 148
descriptive statistics. Statistical analysis was performed using the IBM SPSS v23.0 software 149
(IBM Corporation, Armonk, New York, USA). One-way ANOVA was applied to determine 150
the difference in mean renal length and volume among the age groups. Paired t-test was used 151
to study the difference in terms of renal length and volume between the left and right kidneys, 152
and between sex in specific age groups. The Pearson’s correlation coefficient (r) and simple 153
linear regression were used to assess the relationship between renal volume and length with 154
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somatic parameters (i.e. age, height, weight, BMI and BSA). 95% CI was used in all the 155
statistical analysis, whereby p-value <0.05 was considered as significant different.
156 157
The age-specific renal length was compared with the data recommended by Han and Babcock 158
[12] via intra-class correlation analysis. Additionally, the mean renal volume of each age 159
group obtained from this study was compared with the data published by Leung et al. [11]
160
using the student’s t-test.
161
162 163
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Results 164
165
1. Correlations Between Renal Size and Somatic Parameters 166
167
Renal length between the left and right kidneys in each age group was not statistically 168
significant different (p > 0.05) (refer Supplementary Data). Besides, the mean renal length of 169
the left and right kidneys were not statistically significant different (p > 0.05) between boys 170
and girls, except in the 12.00 - 12.99 age group (p = 0.043) (refer Supplementary Data).
171 172
There was no statistically significant difference between the renal volume of the left and right 173
kidneys, except in the 13.00 - 13.99 (p = 0.003) and 14.00 - 14.99 (p = 0.004) age groups, as 174
shown in Table 2. There was also no statistically significant difference in term of renal 175
volume between boys and girls, except in the 7.00 - 7.99 age group (p = 0.006) (refer Table 176
177 3).
178
Fig. 2 and 3 show the correlations between renal length and volume with various somatic 179
parameters. Results show that the renal length and volume showed good positive correlation 180
with age, height, weight and BSA, but weak correlation with BMI (r = 0.394 for length and 181
0.572 for volume). The order of correlation coefficients, r from strongest to weakest for renal 182
length was height (0.819), BSA (0.763), age (0.719), weight (0.701) and BMI (0.394);
183
whereas for renal volume was BSA (0.813), weight (0.786), height (0.753), age (0.625) and 184
BMI (0.572). All the p-values obtained were <0.05, indicating that the correlations were 185
significant. Table 4 and 5 summarize the r values and linear regression equations derived 186
from the simple linear regression analysis.
187 188
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2. Comparison of Age-Specific Renal Length and Volume 189
190
Comparison of the mean total renal volume in each age group between this study and Leung 191
et al. [11] study is shown in Table 6. The age-specific total renal volumes in our study were 192
significantly lower (p < 0.05) than the data reported by Leung et al, except for the age groups 193
of 6.00 – 6.99 and 11.00 – 11.49 years. On the other hand, the correlation of renal length 194
between our study and Han and Babcock [12] study was plotted in Fig. 4. The results showed 195
a fair agreement (intra-class correlation, ICC = 0.59).
196 197 198
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Discussion 199
200
Similar to other studies, we did not find statistically significant difference in renal length and 201
volume between sex [8,14,2,15] and between the left and right kidneys of the same subject 202
[8,16]. Therefore, it is not necessary to concern about the child’s gender and side of the 203
kidney when examining the kidney size in clinical practice.
204 205
This study revealed that renal length had the strongest correlation with height, which is in 206
agreement with other studies [2,17,18,15,19,7], followed by BSA, age and weight. On the 207
other hand, renal volume correlates the strongest with BSA, followed by weight, height and 208
age. This finding is similar to the study of 1000 Indian children carried out by Otiv et al. [15]
209
and a study by Scholbach et al. [16] involving 624 children in Germany. BMI had weak and 210
moderate correlations with renal length and volume, respectively. This finding is in 211
agreement with many other published studies [20,21,18,22]. Therefore, it is suggested that 212
the four somatic parameters (i.e. height, weight, BSA and age) have strong positive 213
correlation with the renal size, making them all applicable as predictors for normal renal size 214
in children between 6 and 15 year-olds. Although height may statistically be the most reliable 215
parameter to predict renal length, and BSA for volume, we believe that age would be the 216
easiest and most practical approach to be used in clinical practice.
217 218
The age-specific renal length in Thai children showed only moderate correlation (ICC = 0.59) 219
with the nomogram reported by Han and Babcock [12]. Han and Babcock is one of the 220
pioneers who assessed renal dimensions and appearance in normal children using 221
ultrasonography. They highlighted that the dimensions and appearance of normal kidneys on 222
sonogram in newborn and young children is unlike those of older children and adults. They 223
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have subsequently developed nomograms according to age, height, weight and BSA for 224
evaluating normal renal size in children with predicted means and 95% prediction intervals.
225
Among all the parameters, the nomogram according to age is the most commonly used 226
normative standards for evaluating renal size in clinical circumstances. Although the 227
nomogram derived from Han and Babcock’s study was based on an American cohort of 122 228
healthy children, the nomogram has been widely referred in most of the hospitals in Thailand 229
until today, primarily due to the lack of local data.
230 231
In addition, the age-specific renal volume of the Thai children was significantly lower than 232
their Chinese peers [11]. This observation was in line with a preliminary study carried out on 233
101 Thai infants (median age of 1) in Siriraj Hospital, Thailand. Unfortunately, both studies 234
from Han and Bobcock and Leung et al did not reveal the somatic parameters such as height, 235
weight and BSA for the respective age groups in their publications, therefore we were unable 236
to compare the somatic factors between our study and Leung et al. Nevertheless, according to 237
a publication by Zong and Li [23], the weight of the Chinese boys was strikingly heavier than 238
the World Health Organization (WHO) Child Growth Standards at age 6 to 10 years. Their 239
height was also higher than the WHO Standards for boys below 15 years and for girls below 240
13, but was significantly lower when boys over 15 years and girls over 13. This finding has 241
caught attention as many researchers have anticipated that Asian generally has smaller body 242
habitus compared to other populations. The authors explained that the differences between 243
China and WHO standards are mainly caused by the reference population of different ethnics 244
and economy background. In another study [24] the authors investigated the physical growth 245
of children and adolescents in China between 1975 and 2010. It was found that the growth of 246
children and adolescents in China has improved in tandem with economic development over 247
the past 35 years and therefore a new China reference should be developed. In comparison, 248
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Thai children have relatively smaller body habitus as shown in a recent publication [25]. The 249
height and weight in our study population are also smaller than the WHO Standards. Hence, 250
it can be determined that the nomogram of pediatric renal volume derived from Leung et al.
251
was not compatible with the Thai children. We therefore concluded that children of different 252
ethnicity, nationalities and other somatic factors may have different renal growth rates, 253
indicating the need for establishing local reference values for clinical use. The linear 254
regression equations developed from this study may be a useful reference to determine the 255
renal length and volume of Thai children, although further studies should be conducted at 256
different regions in the country.
257 258
There were several limitations in this study. Firstly, the number of subjects recruited was the 259
minimum derived by statistical calculation, which would reflect the lowest limit in a growth 260
chart. As this was the first prospective study of renal length and volume for normal Thai 261
children in various age groups, the sample size should be increased in future studies.
262
Secondly, 2D-US might not be the most accurate tool for renal volume measurement as it 263
might underestimate the results, according to some publications [1,4]. Some studies have 264
actually suggested that three-dimensional ultrasonography (3D-US) is a more reliable tool in 265
measuring renal volume in children. In addition, children in Thailand are multi-ethnics and 266
their renal size may vary between regions and ethnicities. Therefore, more localized studies 267
are needed to compare the renal size between regions and ethnicities. In this study, we 268
assumed that the mean body weight and height were representative of the average children 269
body size across the country.
270
271 272
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Conclusion 273
274
We found good positive correlations between renal sizes and somatic parameters such as 275
BSA, height, weight and age, except BMI. Height appeared to be the most reliable indicator 276
for renal length and BSA for volume, however age could also be used as a practical 277
parameter in estimating the renal size in children between 6 and 15 year-olds. No statistical 278
significant difference was found on renal length and volume between boys and girls, and 279
between the left and right kidneys. The total renal volumes of normal Thai children in our 280
study were significantly smaller than the Chinese cohort [11]. The renal length also showed 281
moderate agreement (ICC = 0.59) with the nomogram recommended by Han and Babcock 282
[12]. Therefore, it can be concluded that the normal renal sizes in children varied from region 283
to region and a local reference standard would be useful in determining the normal renal size 284
in children within the population.
285 286 287 288
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References 289
290
1. Bakker J, Olree M, Kaatee R, de Lange EE, Moons KG, Beutler JJ, Beek FJ (1999) Renal 291
volume measurements: accuracy and repeatability of US compared with that of MR imaging.
292
Radiology 211 (3):623-628 293
2. Gavela T, Sanchez Bayle M, Gomez Mardones G, Gallego S, Martinez-Perez J, Moya MT 294
(2006) [Ecographic study of kidney size in children]. Nefrologia : publicacion oficial de la 295
Sociedad Espanola Nefrologia 26 (3):325-329 296
3. Holloway H, Jones T, Robinson A, Harpen M, Wiseman H (1983) Sonographic 297
determination of renal volumes in normal neonates. Pediatric Radiology 13 (4):212-214 298
4. Kim HC, Yang DM, Lee SH, Cho YD (2008) Usefulness of renal volume measurements 299
obtained by a 3‐dimensional sonographic transducer with matrix electronic arrays. Journal of 300
Ultrasound in Medicine 27 (12):1673-1681 301
5. Schmidt IM, Main KM, Damgaard IN, Mau C, Haavisto A-M, Chellakooty M, Boisen KA, 302
Petersen JH, Scheike T, Olgaard K (2004) Kidney growth in 717 healthy children aged 0–18 303
months: a longitudinal cohort study. Pediatric Nephrology 19 (9):992-1003 304
6. Shin HS, Chung BH, Lee SE, Kim WJ, Ha HI, Yang CW (2009) Measurement of kidney 305
volume with multi-detector computed tomography scanning in young Korean. Yonsei 306
medical journal 50 (2):262-265 307
7. Zerin J, Blane C (1994) Sonographic assessment of renal length in children: a reappraisal.
308
Pediatric radiology 24 (2):101-106 309
8. Chandra J, Mathur S, Mittal S, Mittal K (1999) Sonographic assessment of renal volume in 310
Indian children. The Indian Journal of Pediatrics 66 (2):175-178 311
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9. Geelhoed JM, Kleyburg-Linkers VE, Snijders SP, Lequin M, Nauta J, Steegers EA, van 312
der Heijden AJ, Jaddoe VW (2009) Reliability of renal ultrasound measurements in children.
313
Pediatric nephrology 24 (7):1345 314
10. Rosenbaum DM, Korngold E, Teele RL (1984) Sonographic assessment of renal length in 315
normal children. American Journal of Roentgenology 142 (3):467-469 316
11. Leung VY-f, Chu WC-w, Yeung C-k, Sreedhar B, Liu J-x, Wong EM-c, Metreweli C 317
(2007) Nomograms of total renal volume, urinary bladder volume and bladder wall thickness 318
index in 3,376 children with a normal urinary tract. Pediatric radiology 37 (2):181-188 319
12. Han BK, Babcock DS (1985) Sonographic measurements and appearance of normal 320
kidneys in children. American Journal of Roentgenology 145 (3):611-616 321
13. Khazaei MR, Mackie F, Rosenberg AR, Kainer G (2008) Renal length discrepancy by 322
ultrasound is a reliable predictor of an abnormal DMSA scan in children. Pediatric 323
Nephrology 23 (1):99-105 324
14. Duminda W, Pathirana K, Fernando M, Samarasinghe R, Ananda W, Silva K, 325
Dissanayake C, Mahesh P (2019) Ultrasonographic length of morphologically-normal 326
kidneys in children presented to a premier tertiary healthcare setting of Sri Lanka. BMC 327
nephrology 20 (1):183 328
15. Otiv AS, Mehta K, Ali U, Nadkarni M (2012) Sonographic measurement of renal size in 329
normal Indian children. Indian pediatrics 49 (7):533-536 330
16. Scholbach T, Weitzel D (2012) Body-surface-area related renal volume: a common 331
normal range from birth to adulthood. Scientifica 2012 332
17. Mohtasib RS, Alshamiri KM, Jobeir AA, Saidi FMA, Masawi AM, Alabdulaziz LS, 333
Hussain FZB (2019) Sonographic measurements for kidney length in normal Saudi children:
334
correlation with other body parameters. Annals of Saudi Medicine 39 (3):143-154 335
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18. Behrouzkia Z, Joveini Z, Keshavarzi B, Eyvazzadeh N, Aghdam RZ (2016) 336
Hyperthermia: how can it be used? Oman medical journal 31 (2):89 337
19. Ravikumar N, Anita S, Venkateshwara R (2016) To Determine the Renal Size in Normal 338
Children by Ultrasonography. Journal of Dental and Medical Sciences 15 (4):41-45 339
20. Kim J-H, Kim M-J, Lim SH, Kim J, Lee M-J (2013) Length and volume of 340
morphologically normal kidneys in Korean children: ultrasound measurement and estimation 341
using body size. Korean journal of radiology 14 (4):677-682 342
21. Muthusami P, Ananthakrishnan R, Santosh P (2014) Need for a nomogram of renal sizes 343
in the Indian population–findings from a single centre sonographic study. The Indian journal 344
of medical research 139 (5):686 345
22. Younus N, Raza F, Bhugio S, Zehra N, Gul P, Nizamani W, Younus S (2015) 346
Sonographic measurement of normal renal size and correlation with somatic variables in 347
subset of Karachi Pediatric Population. Pakistan Journal of Medicine and Dentistry 4 (02):23 348
23. Zong X-N, Li H (2013) Construction of a new growth references for China based on 349
urban Chinese children: comparison with the WHO growth standards. PloS one 8 (3) 350
24. Zong X-N, Li H (2014) Physical growth of children and adolescents in China over the 351
past 35 years. Bulletin of the World Health Organization 92:555-564 352
25. Bongsebandhu-phubhakdi C, Suteerojntrakool O, Tempark T (2017) Body size 353
perception in Thai school-aged children. Chulalongkorn Medical Journal 61 (3):343-355 354
355 356 357 358
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Figure Captions:
359 360
Fig. 1. A sample two-dimensional ultrasound image of the kidney obtained using a 2–5 MHz 361
transducer. (a) The maximum renal length (L) was measured along the longitudinal axis of 362
the kidney. (b) The width (W) and thickness (T) were measured in the transverse plane 363
perpendicular to the longitudinal axis of the kidney at the level of the hilum.
364 365
Fig. 2. Scatter plots showing the linear correlations between mean renal length and various 366
somatic parameters 367
368
Fig. 3. Scatter plots showing the linear correlations between mean renal volume and various 369
somatic parameters 370
371
Fig. 4. Intraclass correlation of renal length between Thai children (this study) and the 372
Western data published by Han and Babcock (1985) 373
374 375
376
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Table 1. Sample size according to age group, sex, and demographic data
Age Total
Number
Sex Number Height (cm) Weight (kg) BMI (kg/m2)
6.00 – 6.99 36 Male 20 118.7 ± 4.7 25 ± 8 17.40 ± 4.53
Female 16 116.1 ± 5.0 20 ± 4 14.83 ± 2.37
7.00 – 7.99 35 Male 12 122.3 ± 5.5 29 ± 11 18.69 ± 5.16
Female 23 121.5 ± 6.1 24 ± 6 16.08 ± 3.69
8.00 – 8.99 35 Male 16 127.0 ± 5.7 28 ± 9 17.37 ± 4.30
Female 19 127.3 ± 7.0 27 ± 6 16.32 ± 2.44
9.00 – 9.99 35 Male 17 134.2 ± 10.5 33 ± 10 18.07 ± 4.77
Female 18 130.7 ± 7.4 30 ± 6 17.25 ± 2.44 10.00 – 10.99 34 Male 15 139.1 ± 8.1 38 ± 17 19.11 ± 6.28 Female 19 137.8 ± 6.7 30 ± 7 15.65 ± 2.31 11.00 – 11.99 39 Male 22 145.4 ± 6.2 44 ± 15 20.65 ± 5.80 Female 17 147.5 ± 8.7 37 ± 8 16.88 ± 2.70 12.00 – 12.99 36 Male 18 148.3 ± 8.0 39 ± 14 17.54 ± 4.01 Female 18 149.3 ± 7.4 40 ± 8 17.97 ± 2.96 13.00 – 13.99 35 Male 17 153.9 ± 9.5 48 ± 13 20.38 ± 4.78 Female 18 155.4 ± 5.0 48 ± 11 19.63 ± 4.20 14.00 – 14.99 36 Male 13 165.8 ± 7.6 52 ± 11 18.82 ± 2.73 Female 23 157.3 ± 4.8 49 ± 10 19.14 ± 3.38
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Age (years) Number
Renal Volume (ml)
Left Right p-value
6.00 – 6.99 36 52.37 ± 13.21 54.12 ± 16.62 0.323
7.00 – 7.99 35 57.44 ± 17.07 54.18 ± 15.00 0.180
8.00 – 8.99 35 59.44 ± 17.04 60.30 ± 19.43 0.734
9.00 – 9.99 35 67.44 ± 19.63 70.95 ± 20.99 0.231
10.00 – 10.99 34 71.56 ± 19.78 69.28 ± 23.98 0.391
11.00 – 11.99 39 86.58 ± 20.89 83.88 ± 20.85 0.312
12.00 – 12.99 36 88.27 ± 20.07 85.59 ± 24.50 0.452
13.00 – 13.99 35 95.21 ± 20.32 83.40 ± 20.82 0.003*
14.00 – 14.99 36 100.50 ± 19.52 87.28 ± 23.84 0.004*
*Values of p < 0.05 indicated statistically significant differences.
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Age (years) Left and Right Renal Volume (ml)
Male (M) Female (F)
p-value (M vs. F)
Both Sex
6.00 – 6.99 57.31 ± 15.76 48.16 ± 9.89 0.051 53.25 ± 14.07 106.49 ± 28.14 7.00 – 7.99 64.81 ± 16.15 51.12 ± 11.18 0.006* 55.81 ± 14.45 111.63 ± 28.90 8.00 – 8.99 62.25 ± 17.63 57.87 ± 16.06 0.447 59.87 ± 16.69 119.74 ± 33.38 9.00 – 9.99 74.34 ± 20.40 64.33 ± 15.44 0.110 69.19 ± 18.46 138.38 ± 36.92 10.00 – 10.99 72.19 ± 18.72 69.02 ± 22.40 0.663 70.42 ± 20.62 140.84 ± 41.23 11.00 – 11.99 87.45 ± 19.01 82.35 ± 19.57 0.417 85.23 ± 19.17 170.45 ± 38.34 12.00 – 12.99 84.04 ± 21.98 89.82 ± 17.34 0.388 86.93 ± 19.73 173.86 ± 39.46 13.00 – 13.99 92.58 ± 16.23 86.20 ± 18.19 0.282 89.30 ± 17.32 178.60 ± 34.64 14.00 – 14.99 96.72 ± 16.29 92.29 ± 18.48 0.477 93.89 ± 17.61 187.78 ± 35.23
*Values of p < 0.05 indicated statistically significant differences.
Accepted Article
Age 0.719 y = 5.95 + 0.26*Age Height 0.809 y = 2.03 + 0.05*Height Weight 0.701 y = 6.93 + 0.05*Weight
BMI 0.394 y = 7.08 + 0.09*BMI
BSA 0.763 y = 5.65 + 2.55*BSA
Abbreviations: BMI - Body Mass Index; BSA - Body Surface Area
Accepted Article
Age 0.625 y = 16.88 + 5.45*Age Height 0.753 y = -76.93 + 1.09*Height Weight 0.786 y = 27.54 + 1.30*Weight
BMI 0.572 y = 18.94 + 3.07*BMI
BSA 0.813 y = -3.68 + 66.93*BSA
Abbreviations: BMI - Body Mass Index; BSA - Body Surface Area
Accepted Article
Age (years)
This study
Leung et al. (2007)
p-value Number Mean SD Number Mean SD
6.00 - 6.49 6.50 - 6.99
17 19
113.71 100.04
26.95 28.30
173 130
123.79 132.18
12.04 12.01
0.146
<0.001*
7.00 - 7.49 7.50 - 7.99
17 18
114.21 109.19
33.31 24.75
142 137
137.00 144.05
12.11 13.26
0.013*
<0.001*
8.00 - 8.49 8.50 - 8.99
20 15
116.99 123.42
35.50 31.16
127 79
151.08 156.15
14.40 11.37
<0.001*
0.001*
9.00 - 9.49 9.50 - 9.99
19 16
130.67 147.55
35.61 37.46
147 79
163.69 168.57
11.93 11.28
<0.001*
0.041*
10.00 - 10.49 10.50 - 10.99
17 17
143.89 137.79
49.12 32.77
125 79
174.16 183.18
10.39 12.69
0.022*
<0.001*
11.00 - 11.49 11.50 - 11.99
19 20
176.04 165.15
45.87 29.77
104 50
188.03 195.24
12.13 11.12
0.272
<0.001*
12.00 - 12.49 12.50 - 12.99
19 17
175.69 171.82
39.90 40.09
90 50
201.82 208.46
11.65 12.56
0.011*
0.002*
13.00 - 13.49 13.50 - 13.99
22 13
181.85 173.12
34.73 35.17
87 42
215.00 218.30
16.63 14.83
<0.001*
<0.001*
14.00 - 14.49 14.50 - 14.99
14 22
182.78 190.97
15.13 43.58
90 45
225.39 230.14
16.98 14.43
<0.001*
<0.001*
*Values of p < 0.05 indicated statistically significant differences.
